Polypeptide hormones and bioamines which appear to produce their effects on differentiated function via cAMP, exert control over synthesis of specific proteins in their target tissues. Two model systems, porcine parotid and pancreas, in which cAMP and various hormones rapidly induce systhesis of large amounts of a specific protein, alpha-amylase, have been chosen for study. The rapid stimulation of alpha-amylase synthesis by cAMP and hormones in these tissues appears not to require new RNA synthesis suggesting translational control or protein synthesis by these hormones. Mechanisms by which hormones could regulate translation of mRNAs coding for inducible proteins include alteration in mRNA-associated proteins or, in the translational apparatus, the site of translational control by cAMP will be defined by reconstitution experiments using homologous and heterologous cell-free protein-synthesizing system. mRNA is associated with specific proteins of functional significance; isolation of purified alpha-amylase mRNA-protein complexes (mRNP) and total cellular MRNPs will allow definition of their putative roles in cAMP-mediated translational control. Ribosomal proteins and translation factors will also be evaluated as sites of hormonal action. These possibilities will be studied with particular emphasis on the role of phosphorylation of a regulatory protein by cAMP-dependent protein kinase. Sustained synthesis of a specific protein by cAMP eventually involves transcription of new mRNA. Ability of nuclei and chromatin isolated from control and hormone-treated tissue to direct synthesis of alpha-amylase mRNA will be stuied. The effect of cAMP, cAMP receptor protein complex, and cAMP-dependent protein kinase in transcription of alpha-amylase mRNA will be quantitated using DNA - RNA hybridization techniques.